List Telnet sessions

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

The readOnlyHint annotation already covers the safety profile. The description adds useful scoping ('visible... started by this MCP server process') but leaves the term 'visible' undefined and does not disclose return format or pagination behavior. This adds context beyond annotations but not rich behavioral detail.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

A single, front-loaded sentence with no filler. Every word adds meaning: 'visible', 'Windows Telnet sessions', and 'started by this MCP server process' all contribute to the tool's purpose and scope.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a no-parameter, read-only list tool, the description is mostly adequate: it states what is listed and the process scope. However, with no output schema, the description should hint at what the returned session list contains (e.g., IDs, names), and the ambiguous 'visible' could confuse an agent. This is a minor but real gap.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The tool has zero parameters, so the input schema is complete and there is nothing for the description to clarify. Baseline of 4 is appropriate; no parameter documentation is needed and the description correctly avoids inventing parameter details.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description uses a specific verb ('Lists') and resource ('visible Windows Telnet sessions started by this MCP server process'), which clearly defines scope. It does not explicitly name a sibling tool for differentiation, but the 'started by this MCP server process' qualifier distinguishes it from broader session queries.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

There is no guidance on when to use this tool versus alternatives like telnet_status or telnet_check. The description implies it is for enumerating sessions, but it does not state exclusions or conditions that would route an agent to a sibling tool.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.